Red Line

In a message dated 3/26/2003 4:04:38 PM Eastern Standard Time,
dave at WILTON.NET writes:
> Use of "red line" to mean a figurative trip wire:
Possibly from automobiles, many of which have a red line on the speedometer
showing a speed you are not to exceed? On airplanes every speedometer has
such a red line at a speed known as the "VNE" ("never-exceed velocity") plus
a yellow arc (caution range), green arc (normal operating speed range), and
white arc (speed range for operating with fully extended flaps).
Also there is the phrase "the thin red line", referring if I remember
correctly to the British Army in its Imperial days (that is, the days before
modern weaponry made riflemen hug the ground and wear camouflage).
Much less likely that it is from civil rights, referring to the practice of
some lenders of not providing mortgages for black neighborhoods, and I
suppose also applied to other discriminatory practices.
James A. Landau
systems engineer
FAA Technical Center (ACB-510/BCI)
Atlantic City Int'l Airport NJ 08405 USA